This may sound like a ridiculous question, but to this day I have not figured it out: What EXACTLY causes a bicycle to pull hard to one side (more often to the left I have experienced) when you are seated, riding, and remove your hands from the bars?
Some bikes pull so hard that you have to grab that bars within a second of letting go (or else you will take a dive.)
For years I thought this pulling was something as simple as one of the wheels not being aligned (in the fork or frame. I also theorized that perhaps the rear triangle of the bicycle was out of alignment. I also suspect that it may be due to the head tube not being in perfect alignment with the seat tube. My last "guess" would be that the "caster" angle of the fork and/or head tube was at some point in the bicycle's life altered (knocked out of alignment) owing to a collision possibly into a parked car, a wall, tree, or what have you.
Does anyone have any input as to why some bicycles do not have a sense of "balance?" I am at a loss to explain this phenomenon.
Ted Baer
Palo Alto, CA